Rationale: Adaptive behaviours, particularly those related to resource harvest and the time available for fitness-enhancing activities, may serve as suitable surrogates for fitness.

Methods: I explore this potential link between behaviour and eco-evolutionary dynamics with controlled field experiments. The experiments manipulated densities of meadow voles foraging in large replicated enclosures. I used the lock-step connection between resource harvest and fitness to generate three fitness surrogates: giving-up densities from artificial resource patches, quitting-harvest rates, and time available for non-foraging behaviours that enhance fitness.

Results: Per capita consumption from food trays did not change with population size. Time allocated to foraging increased with population density. Quitting-harvest rates in both safe and risky patches declined linearly with population density. The total amount of time necessary for a new individual to acquire sufficient energy for maintenance increased hyperbolically. Invasion landscapes based on the three fitness surrogates yielded the same behaviourally and evolutionarily stable strategy (ESS) of habitat selection. But the fitness benefits, subsequent convergence towards the ESS, and potential variation about the ESS, varied.

Conclusions: Adaptive foraging behaviour is a reliable and rapid metric for assessing the evolutionary stability of habitat selection. This proof of concept suggests that behavioural metrics may play a prominent role in assessments of other strategies. We may even be able to use behavioural metrics to forecast ecological and evolutionary futures associated with ecological change.

Subscribing institutions/libraries may grant individuals the privilege of making a single copy of an EER article for non-commercial educational or non-commercial research purposes. Subscribing institutions/libraries may also use articles for non-commercial educational purposes by making any number of copies for course packs or course reserve collections. Subscribing institutions/libraries may also loan single copies of articles to non-commercial libraries for educational purposes.

All copies of abstracts and articles must preserve their copyright notice without modification.